watching a load of holmes on homes programs, they use something called a weeping tile (don't know why they call it that) but it's a plastic pipe with holes in it, covered in some sort of cloth material, that you lay at the bottom of the walls in the soi and stone and crap which collects all the water and sends it to the drains

might be worth a go in your situation seeing as you are going to have a lot of earth and stuff to sock the water up

http://en.wikipedia.org/wiki/Weeping_tile

and

http://homes.winnipegfreepress.com/w...-grief/id-921/